and about your first question:
some viral deseases can be cured, using enzyme inhibitors. for example, neuroaminidase inhibitors such as oseltamivir can cure the flu.
some viral deseases cannot be cured, regardless of treatment. the most famous example is the HIV virus. regardless of using inhibitors on 4-5 stages of its reproductive cycle, the virus still kills its host with a 100% efficiency.

"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

- Viruses, when active, are mostly using processes done regularly in the host cell, but now those processes are making viruses. You can't poison the processes without messing up lots of noninfected cells doing their regular business. We're lucky that HIV does a couple of things that regular cells don't.

- Between host cells, viruses aren't doing really anything that can be poisoned - they're kind of like wandering, set traps that "go off" when they contact a new host cell. Some treatments (and antibodies) go after the free viruses, but it's tough when they're really not that active.

Bacteria and other disease organisms have unique, poisonable chemistry and are usually accessible between hosts, giving many treatment approaches.

While your teacher was technically incorrect, and antibiotics can not by any means destroy a virus, she may have been correct in a concept and mis conveyed it to you. Many common illnesses are caused by bacteria which are altered by bacteriophages (a type of virus). So, what the teacher could have meant to say was that the bacteria which are influenced by these viruses can be killed by anti-biotics, which in turn could in theory stop the illness by illiminating the host range which the virus is able to act upon.

intali wrote:So, what the teacher could have meant to say was that the bacteria which are influenced by these viruses can be killed by anti-biotics, which in turn could in theory stop the illness by illiminating the host range which the virus is able to act upon.

Phages are not going to attack human cells, so since they are not a cause, bacteria or no bacteria (treated with antibiotics) will not change your health.
In any case antibiotics cannot cure viral diseases. But they can be used in association with antiviral, when the viral disease is weakening your immune system then making you more susceptible to bacterial infection, as a prevention against opportunistic infections.

Patrick

Science has proof without any certainty. Creationists have certainty without
any proof. (Ashley Montague)

canalon wrote:Phages are not going to attack human cells, so since they are not a cause, bacteria or no bacteria (treated with antibiotics) will not change your health.

Even hough the phages may not attack the human cells directly, they may infect the bacteria always present within the body. When the phages infect the bacteria they may cause the bacteria to produce the toxins that cause the disease. So, if you use an antibiotic to destroy the bacteria that are hosting the phage genome, and thus causing the illness, you stop the production of the toxins, which cures the disease. Obviously this isn't the case with all human viral diseases, but it is true for some.

Some virulence gens are indeed carried on prophages or other phage remnant, I agree. But calling a bacterial infection by a bacteria where one among a usually very large number of genes involved in the virulence is uite a stretch that you should not do. It is as if I was saying that a windows antivirus can prevent prevent car accident because one model use Windows to control the car eletronics (don't laugh I remember seeing one concept car with some drive by wire controlled by windows...). Not completely false, but very irrelevant.

Patrick

Science has proof without any certainty. Creationists have certainty without
any proof. (Ashley Montague)